/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb.db.mpp.plan.planner.plan.node.source;

import com.google.common.collect.ImmutableList;
import org.apache.iotdb.common.rpc.thrift.TDataNodeLocation;
import org.apache.iotdb.db.mpp.common.header.ColumnHeaderConstant;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanNode;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanNodeId;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanNodeType;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanVisitor;

import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.List;
import java.util.Objects;

public class ShowQueriesNode extends VirtualSourceNode {

    public static final List<String> SHOW_QUERIES_HEADER_COLUMNS =
            ImmutableList.of(
                    ColumnHeaderConstant.QUERY_ID,
                    ColumnHeaderConstant.DATA_NODE_ID,
                    ColumnHeaderConstant.ELAPSED_TIME,
                    ColumnHeaderConstant.STATEMENT);

    public ShowQueriesNode(PlanNodeId id, TDataNodeLocation dataNodeLocation) {
        super(id, dataNodeLocation);
    }

    @Override
    public List<PlanNode> getChildren() {
        return ImmutableList.of();
    }

    @Override
    public void addChild(PlanNode child) {
        throw new UnsupportedOperationException("no child is allowed for ShowQueriesNode");
    }

    @Override
    public PlanNode clone() {
        return new ShowQueriesNode(getPlanNodeId(), getDataNodeLocation());
    }

    @Override
    public int allowedChildCount() {
        return NO_CHILD_ALLOWED;
    }

    @Override
    public List<String> getOutputColumnNames() {
        return SHOW_QUERIES_HEADER_COLUMNS;
    }

    @Override
    public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
        return visitor.visitShowQueries(this, context);
    }

    // We only use DataNodeLocation when do distributionPlan, so DataNodeLocation is no need to
    // serialize
    @Override
    protected void serializeAttributes(ByteBuffer byteBuffer) {
        PlanNodeType.SHOW_QUERIES.serialize(byteBuffer);
    }

    @Override
    protected void serializeAttributes(DataOutputStream stream) throws IOException {
        PlanNodeType.SHOW_QUERIES.serialize(stream);
    }

    public static ShowQueriesNode deserialize(ByteBuffer byteBuffer) {
        PlanNodeId planNodeId = PlanNodeId.deserialize(byteBuffer);
        return new ShowQueriesNode(planNodeId, null);
    }

    @Override
    public boolean equals(Object o) {
        return super.equals(o);
    }

    @Override
    public int hashCode() {
        return Objects.hash(super.hashCode());
    }

    @Override
    public String toString() {
        return "ShowQueriesNode-" + this.getPlanNodeId();
    }
}
